The last 18 hours or so went better than those before them (as described in the previous post). The server could boot from a CD, and with the right CD and a bit of guided prodding it was in a condition such that
jmaynard could patch it up remotely.
While he did that, I looked at the furnace. It wasn't the motor that circulates air through the ductwork. It was the motor that blows exhaust gasses outside ("high efficiency" furnace - no chimney as such). There wasn't anything I could do but clean up a bit and make things easy for the repairman.
Once the server was back, conmicro.cx wasn't resolving, but it was reachable by numeric IP. I didn't do anything there, at least not beyond answer a phone call from someone wondering where Hercules went.
Without the furnace working, it was a night of thick quilts, an electric heating pad, and a Santa hat as a nightcap - hey, it works. The temperature in the living room had dropped to 55 F when I checked it this morning. It was a bit warmer upstairs. At least this happened in late March and not January.
There's heat on in the house again, and not just the blinds open to the south. It didn't take long for the repairman to replace that motor.